<template>
	<view
		class="u-col"
		:class="[
			'u-col-' + span
		]"
		:style="{
			padding: `0 ${Number(gutter)/2 + 'rpx'}`,
			marginLeft: 100 / 12 * offset + '%',
			flex: `0 0 ${100 / 12 * span}%`,
			alignItems: uAlignItem,
			justifyContent: uJustify,
			textAlign: textAlign
		}"
		@tap="click"
	>
		<slot />
	</view>
</template>

<script>
/**
	 * col 布局单元格
	 * @description 通过基础的 12 分栏，迅速简便地创建布局（搭配<u-row>使用）
	 * @tutorial https://www.uviewui.com/components/layout.html
	 * @property {String Number} span 栅格占据的列数，总12等分（默认0）
	 * @property {String} text-align 文字水平对齐方式（默认left）
	 * @property {String Number} offset 分栏左边偏移，计算方式与span相同（默认0）
	 * @example <u-col span="3"><view class="demo-layout bg-purple"></view></u-col>
	 */
export default {
  name: 'u-col',
  props: {
    // 占父容器宽度的多少等分，总分为12份
    span: {
      type: [Number, String],
      default: 12
    },
    // 指定栅格左侧的间隔数(总12栏)
    offset: {
      type: [Number, String],
      default: 0
    },
    // 水平排列方式，可选值为`start`(或`flex-start`)、`end`(或`flex-end`)、`center`、`around`(或`space-around`)、`between`(或`space-between`)
    justify: {
      type: String,
      default: 'start'
    },
    // 垂直对齐方式，可选值为top、center、bottom
    align: {
      type: String,
      default: 'center'
    },
    // 文字对齐方式
    textAlign: {
      type: String,
      default: 'left'
    },
    // 是否阻止事件传播
    stop: {
      type: Boolean,
      default: true
    }
  },
  data() {
    return {
      gutter: 20, // 给col添加间距，左右边距各占一半，从父组件u-row获取
    }
  },
  created() {
    this.parent = false
  },
  mounted() {
    // 获取父组件实例，并赋值给对应的参数
    this.parent = this.$u.$parent.call(this, 'u-row')
    if (this.parent) {
      this.gutter = this.parent.gutter
    }
  },
  computed: {
    uJustify() {
      if (this.justify == 'end' || this.justify == 'start') return 'flex-' + this.justify
      else if (this.justify == 'around' || this.justify == 'between') return 'space-' + this.justify
      else return this.justify
    },
    uAlignItem() {
      if (this.align == 'top') return 'flex-start'
      if (this.align == 'bottom') return 'flex-end'
      else return this.align
    }
  },
  methods: {
    click(e) {
      this.$emit('click')
    }
  }
}
</script>

<style lang="scss">
	@import "../../libs/css/style.components.scss";

	.u-col {
		/* #ifdef MP-WEIXIN || MP-QQ || MP-TOUTIAO */
		float: left;
		/* #endif */
	}

	.u-col-0 {
		width: 0;
	}

	.u-col-1 {
		width: calc(100%/12);
	}

	.u-col-2 {
		width: calc(100%/12 * 2);
	}

	.u-col-3 {
		width: calc(100%/12 * 3);
	}

	.u-col-4 {
		width: calc(100%/12 * 4);
	}

	.u-col-5 {
		width: calc(100%/12 * 5);
	}

	.u-col-6 {
		width: calc(100%/12 * 6);
	}

	.u-col-7 {
		width: calc(100%/12 * 7);
	}

	.u-col-8 {
		width: calc(100%/12 * 8);
	}

	.u-col-9 {
		width: calc(100%/12 * 9);
	}

	.u-col-10 {
		width: calc(100%/12 * 10);
	}

	.u-col-11 {
		width: calc(100%/12 * 11);
	}

	.u-col-12 {
		width: calc(100%/12 * 12);
	}
</style>
